The invention concerns a pliable bentwood laminate (i.e. after processing curved into a moulding), with an intermediate layer, in particular forming a central layer, having a first and a second surface side (facing away from one another), wherein a first timber layer is provided, in particular is bonded with adhesive onto the first surface side, and a second timber layer is provided, in particular is bonded with adhesive onto the second surface side. Furthermore the invention concerns a curved moulding manufactured from such a bentwood laminate, wherein the bentwood laminate of the curved moulding is no longer pliable in its processed form, but rather is stiffened, in particular by virtue of the provision of at least one covering layer.
WO 2009/138197 A 1, which is outside the subject area, is concerned with mouldings of balsawood that are stiff in bending, wherein as an intermediate step in the manufacture of such a moulding it is of known art to manufacture a block that is stiff in bending from a multiplicity of veneers arranged one above another, and to process this into cross-cut timber sheets.
From DE 201 08 858 U1 a furniture manufacture panel that is stiff in bending is of known art; as an intermediate or core layer this has what is, in comparison to the other layers, a very thick balsawood sheet, the fibres of which are aligned at right angles to the surface area of the panel, as a result of which a stiff lightweight construction panel for land vehicles and aircraft is obtained. The above-cited balsawood intermediate layer takes the form of solid timber, on whose outer faces timber veneer layers can be provided for purposes of decoration.
EP 2 119 540 A 1, which is also outside the subject area, is concerned with rigid mouldings of balsawood timbers, wherein the moulding is formed from a multiplicity of small balsawood sections, which are bonded by means of adhesive located between them. The moulding of known art is not pliable.
From GB 797 026 a two-layer balsawood structure for the manufacture of liquefied gas tanks is of known art. Two layers of solid balsawood are deployed, whose fibre directions are orientated at right angles to one another. With the two-layer arrangement of known art only very large bending radii can be manufactured, such as occur in liquefied gas tanks.
In addition to the above-cited balsawood applications, bentwoods, traditionally designated as bendable plywood, are well known. The bentwoods of known art are often used as central layer structures of curved mouldings, wherein for many applications, e.g. in furniture construction, it is necessary to bond together with adhesive a multiplicity of bendable plywood timbers, in each case multi-layer, and initially separate from one another, so as to achieve a sufficient wall thickness; however, this is disadvantageous in many respects. On the one hand, the manufacturing process for the resulting curved moulding is more complex, since many operational steps are necessary. On the other hand the direct bonding with adhesive of bendable plywood timbers leads in practice, without a barrier between the bendable plywood timbers, to a joint with a comparatively low stiffness.
Furthermore, the minimum bending radii that can be achieved with the bendable plywood timbers of known art are set within comparatively tight limits, so that when implementing these small bending radii the result would be damage of the bentwood, or, if necessary, a plurality of very thin plywood layers would have to be deployed.
Also, in the case of existing timbers, in particular with a comparatively large thickness, the large restoring forces acting during the bending process are disadvantageous, since they render any further processing into curved mouldings more difficult.